In the past, differentiation therapy has been discussed as a small portion of large meetings on cell differentiation. In the last three years we have established a forum where discussion of this subject is done in depth, with both basic and clinical data presented in detail. In view of the recent interest in the conceptual use of differentiation therapy in clinical trials throughout the world, we believe that there is a need to have an on-going workshop conference which brings together scientists and clinicians with proven scientific interest in this field. We have already established a communications network of 10 working sub- groups, comprised of over 125 participants, all of whom have demonstrated an interest in the induction of differentiation as a possible therapy. Our original concept was that each participant be committed to participate in the meeting for a period of three years. To that end working sub-groups were established which fit the scientific expertise of the participant, and each has continued to work within this frame work for the last three years. At the Third Conference in Sardinia, sub-group co-chairmen organized and presented the progress of their working sub- groups and all of the participants reported on their recent studies in the field. As was anticipated following the Second Conference, all of the participants continued to communicate on a regular basis, and several important collaborations have resulted from this. The abstracts from the Third Conference have been published and the reports from the working sub-groups have been distributed and submitted for publication (see attached). It was determined, based upon the enthusiasm of all participants, that the conferences should continue on a regular basis and these participants have committed themselves to continued collaboration for another four years. It is our belief that this structure will facilitate the development of differentiation therapy as a viable clinical tool.